For manufacturing power devices, so-called float zone semiconductor substrate is used, which is doped during manufacturing of the semiconductor substrate. A cost-efficient alternative are so-called Czochralski semiconductor materials which can be provided as large diameter wafers. FZ substrates are limited to 200 mm. Semiconductor material manufactured by using the Czochralski process exhibit a high concentration of oxygen which diffuses in the material during manufacturing. FZ materials have a much lower oxygen concentration.
Interstitial oxygen may act as unwanted doping centres or influences the diffusion of dopants. It is therefore desire to have a cost-efficient semiconductor material with a low oxygen concentration.
In view of the above, there is a need for improvement.